The present invention relates to a method and apparatus for aligning stacked paper sheets or the like so that the neighboring sheets accurately overlap each other. More particularly, the invention relates to improvements in a method and apparatus for aligning sheets in a stack which contains at least one sheet or panel whose dimensions exceed the dimensions of the other sheets. Still more particularly, the invention relates to a method and apparatus for aligning the sheets or panels of a stack wherein a marginal portion of at least one sheet or panel or panel extends beyond one edge face of the major portion of the stack.
It is often necessary to manipulate stacks of paper sheets or the like prior to conversion into steno pads, note books, calendars, exercise books or analogous stationery products in order to ensure that each and every sheet or panel (hereinafter called sheet) of a stack will accurately register with (i.e., overlie or be overlapped by) the neighboring sheet or sheets. The aligning procedure is relatively simple, at least in most instances, if the entire stack consists of identical sheets. Thus, it is customary to cause one edge face of the stack to abut against a suitable stop while the stack rests on a supporting surface, and the edge face which is located opposite the one edge face is engaged by a suitable tool to shift the projecting or misaligned sheets toward the stop. Such procedure is quite satisfactory and can be carried out by resorting to relatively simple instrumentalities, as long as the dimensions of all sheets in the stack are identical. However, if the stack contains at least one sheet (which may be an outermost sheet or an intermediate sheet) whose dimensions exceed the dimensions of other sheets in the stack, the just discussed conventional procedure is unsatisfactory because the aforementioned shifting tool is likely to damage the adjacent marginal portion or portions of the larger sheet or sheets during movement toward the stop. Relatively large intermediate or outermost sheets are often desirable to constitute separators between smaller piles of sheets within a larger stack, to facilitate convenient and rapid opening of a book or pad at a desired page, or for other purposes.